Double-drum washing machine with sliding doors



Oct. 25, 1966 K. SCHWAMM 3,280,603

DOUBLE-DRUM WASHING MACHINE WITH SLIDING DOORS Filed Dec. 14, 1964 5 Sheets-Sheet l Jn ven for KARL SCHWAMM ATTYS.

Oct. 25, 1966 K. SCHWAMM DOUBLE-DRUM WASHING MACHINE WITH SLIDING DOORS Filed Dec. 14, 1964 5 Sheets-Sheet 2 Jnven for 2a 3/ 32 Fi 26 1m-- I l I I l i ilfil l jffjlilll 111::

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Oct. 25, 1966 K. SCHWAMM 3,280,603

DOUBLE-DRUM WASHING MACHINE WITH SLIDING DOORS Filed Dec. 14, 1964 5 Sheets-Sheet 3 Jnvem0r-' KARL SCHWAM ATTYJ'.

United States Patent DQUBLE-DRUM WASHING MACHINE WITH SLEDING DQORS Karl Schwarnm, Dusseldorf, Germany, assignor to Gehr. Poensgcn Dussedorf-Rath, Germany Filed Dec. 14-, 1964, Ser. No. 418,130

Claims priority, application Germany, Dec. 14, 1963,

8 Claims. (Cl. 68-139) This invention relates to double-drum washing machines, and more specifically to a double-drum washing machine having an outer drum and a rotatably driven inner drum which are provided with sliding doors.

Opening of the doors of the outer and inner drums of such washing machines was hitherto generally effected by hand. It is, however, already known to couple the sliding door of the outer drum with the frame of the washing machine and to open and close the sliding door by rotating the outer drum. Opening and closing of the door of the inner drum of this known washing machine is effected by hand.

It is the object of the present invention to ensure automatic opening both of the door of the outer drum and of the door of the inner drum.

To achieve this object, it is proposed according to the invention that for opening the sliding doors the sliding door of the outer drum be adapted to be coupled with the inner drum and the sliding door of the inner drum be adapted to be coupled with the outer drum. By the invention it is thus possible to open both sliding door by rotating at least one drum, preferably the inner drum, While utilizing the driving force for the drum.

According to an important feature of the invention, opening of the sliding doors is effected by two successive rotations of the inner drum in opposite directions, the sliding doors being likewise successively coupled with the inner and outer drums in the above mentioned sense.

The couplings for connecting the sliding doors with the inner and outer drums include preferably pneumatically operated claws which are engageable with pins of the respective other member to be coupled. The claws may also be operated hydraulically or electromagnetically, if desired also mechanically. The pins may be elastically mounted in the direction of movement of the claws against spring action.

In a preferred embodiment of the invention, in the couplings for connecting the sliding door of the outer rum with the inner drum, pressure cylinders with claws are arranged on the sliding door of the outer drum and ins on the outer edge of end walls of the inner drum. n such an arrangement the ressure cylinders may be dispo e on the outer side of the sliding door of the outer d um and the claws may extend through openings in the sliding door of the outer drum into the interior of the outer drum.

in accordance therewith, in the couplings for connecting the sliding door of the inner drum with the outer drum, pressure cylinders are mounted on end Walls of the outer drum and pins on the edge of the end walls of the inner drum, the claws being passed through the end walls of the outer drum.

The control of the individual operations during opening and closing of the sliding door is performed by limit switches which may run on to operating cams and serve to control the drive of the inner drum so that the inner rum will be rotated by the necessary amounts in both directions, and further effect engagement and disengagement of the couplings. These limit switches may be mounted on a supporting member fixed to the outer drum, whereas the operating cams may be provided on a shaft of the rotatable inner drum or on a carrier connected to the shaft and are arranged for co-operation with the limit switches.

The invention consists, however, not only in the aforementioned claimed individual features but also in every possible combination of these features.

An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings in which:

FIG. 1 is a schematic cross-sectional view of a washing machine according to the invention in closed condition;

FIG. 2 is a view similar to FIG. 1 but showing the outer drum of the washing machine in open condition;

FIG. 3 is a similar view, showing both the outer and inner drums of the washing machine in open condition;

FIG. 4 is a schematic side elevational view of the washing machine in the condition of FIG. 2;

FIG. 5 is a fragmentary schematic longitudinal section through the washing machine, showing the coupling between the inner drum and the sliding door of the outer drum, and

FIG. 6 is a fragmentary schematic side elevational View, partly in section, of the washing machine in the condition of FIG. 2, showing the coupling between the outer drum and the sliding door of the inner drum.

The drawings show an embodiment of a double-drum washing machine as proposed by the invention which comprises a stationary outer drum 10 and a rotatable inner drum 11. The inner drum 11 is driven by a motor 12 through the intermediary of a transmission 13, a friction gear 14 and a chain drive 15 with a peripheral speed of e.g. 0.1 to 0.2 m./sec. A sprocket wheel 16 as the last member of the chain drive 15 is mounted on a shaft 17 of the inner drum 1!, a shown especially in Fig. 4. The shaft 17 or stub shafts of the inner drum 11 are rotatably mounted on both sides in bearings 18 and 19 on end walls 2%) and 21 of the outer drum 10.

Both drums, i.e. the outer drum 10 and the inner drum 11, are provided with sliding doors 22 and 23, respectively. These sliding doors in the illustrated embodiment extend over the entire length of the drums and cover a partial region of the cylindrical drums in circumferential direction. When opening the sliding doors 22 and 23 (see FIGS. 1 to 3) they are shifted parallel to the cylinders of the drums 1t and 11 in circumferential direction whereby overlapping openings in both drums become free through which laundry can be charged into or discharged from the inner drum.

In the illustrated embodiment the inner drum 11 is subdivided by a radial partition 24 into two drum halves each of which can be filled with laundry and which therefore are both equipped with a sliding door 23 and 25, respectively. Both drum halves are charged through one and the same sliding door 22 of the outer drum.

Opening of the individual sliding doors 22, 23 and 25 of the outer and inner drums is to be effected according to the invention by rotation of the inner drum 11. For this purpose provision is made of couplings which connect the sliding doors alternately with the outer drum or the inner drum.

For opening the sliding door 22 of the outer drum 10 it is necessary to provide a connection of this sliding door with the inner drum 11. For this purpose couplings 26 are provided at both ends of the outer drum, which are operated according to an automatically controlled program. As shown especially in FIG. 4, the couplings 26 for opening the sliding door 22 include claws 27, movably fixed on the sliding door 22 and adapted for engagement with pins 28 secured to annular flanges 29 of end walls 30 and 31 of the inner drum 11. The claws 27 are preferably pneumatically operated. For this purpose the claws are connected to pistons 32 which are operated by compressed air and movable in cylinders 33 fixed on the outer side of the sliding door 22. The claws 27 guided along the inner side of the sliding door 22 (see FIG. are connected with the piston rods of the pistons 32 by means of Webs 34 passing through openings in the sliding door 22. Pressure medium is fed into the cylinders 33 through conduits 35 which are preferably constructed as hoses so that they can follow the movements of the cylinders 33 when the sliding door is being opened or closed.

For opening the sliding door 23 or 25 of the inner drum 11 provision is made of couplings 36 of similar construction. These couplings include preferably likewise pneumatically operated claws 37 which are connected to pistons 38 operated by compressed air and movable in cylinders 39 fixed on the outer side of the end walls 20 and 21 of the outer drum it). As shown especially in FIG. 6, the pistons rods of the pistons movable in the cylinders 39 are passed through the end walls 29 and 21 of the outer drum so that the claws 37 are positioned in the interior of the outer drum.

On the annular flange 29 of the inner drum 11 there are again provided pins 40 with which the claws 37 of the couplings 36 can engage. However, different from the construction of the couplings 26, these pins 41 are elastically mounted against spring action, e.g. fixed on a bar 42 loaded by a spring 41. Pressure medium is fed to the cylinders 39 of these couplings 36 through rigid conduits 43.

In the illustrated embodiment each sliding door is provided with two of the above-described couplings 26 and 36, respectively. 1

When opening the sliding doors 22 and 23 the following motional actions take place according to the invention:

First the coupling 26 for the sliding door 22 of the outer drum 10 is brought into engagement (FIG. 1). Then the sliding door 22 is movedinto the open position (FIG. 2) by rotating the inner drum 11 in accordance with the peripheral dimension of the sliding door 22. The driving motor 12 is switched off, the coupling 26 disengaged and the coupling 36 engaged. Then the inner drum 11 is driven by the motor 12 in the reverse direction of rotation. During this action the sliding door 23 of the inner drum 11 is firmly held 'by the coupling 36 and opened due to the rotation of the inner drum. In the end position shown in FIG. 3 both doors are opened and the inner drum or the respective half of the inner drum can be charged or discharged. When closing the sliding doors 22 and 23 the above-described motional actions occur in reverse order.

For controlling the above-described operation the invention provides limit switches which are arranged to switch ofi the driving motor 12 and to engage or disengage the couplings 26 and 36 in the different positions. Such limit switches designated by 44, 45 and 46 which are of usual construction, are mounted in a number corresponding to the control program on a ring 47 fixed to the outer drum 10 or the end wall 21. A cam disc 49 equipped with operating cams 48 is secured to the sprocket wheel 16 which is arranged for rotation together with the shaft 17 of the rotatable inner drum 11. The cams 48 of this cam disc cooperate with the limit switches 44, 45 and 46 in the above-described manner. The limit switches effect disconnection of the driving motor 12 and supply of compressed air to the pressure cylinders of the couplings with the inner drum in a predetermined position in thedirection of rotation. A sequence switch 50 serves to re-start the driving motor after decoupling or coupling together.

The invention may be used in connection with washing machines of various designs. For example, also sliding doors of Washing machines having two rotatable drums can be opened the above-described manner and so can sliding doors of a washingv machine wherein the outer drum is rotatable whereas the inner drum'is stationary. Furthermore, it is possible to operate the individual claws of the couplings in a difierent manner, for example hydraulically or magnetically. Finally, the individual couplings may be arranged at such distance apart. that both sliding doors are simultaneously opened by rotating the inner drum in one direction by an amount corresponding 1 to the opening path.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof.

The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated 'by the appended claims rather than by the foregoing description.

I claim:

1. A double-drum washing machine comprising an outer stationary drum, a rotatably driven inner drum arranged in said outer drum, a sliding door on said outer drum and at least one sliding door on the inner drum, coa-cting means on the sliding door of the outer drum and the inner drum to form a coupling therebetween and coacting means between the sliding door of the inner drum' and the outer drum and operable upon rotation of the inner drum for opening and closing said inner drum sliding door, the opening of the sliding doors being effected by two successive rotations of the inner drum in opposite directions.

2. A washing machine as claimed in claim 1, wherein the couplings for connecting the sliding doors with the inner and outer drums include claws and pins on the respective doors and drums to be coupled, said claws being engageable with said pins. 1

3. A washing machine as claimed in claim 2, wherein the claws are pneumatically operable.

4. A Washing machine as claimed in claim 2, wherein the pins are elastically mounted in the direction of movement of the claws against spring action.

5. A washing machine as claimed in claim 4, wherein end walls are provided on the outer and inner drums, the couplings further including pressure cylinders on the end walls, and the pressure cylinders of the couplings for connecting the sliding door of the outer drum with the inner drum being arranged on the sliding doorof the outer drum and the pins on the outer edge of the end walls of the inner drum.

6. A washing machine as claimed in claim 5, wherein openings are formed in the sliding door of the outer drum, the pressure cylinders being disposed on the outer side of the sliding door of the outer drum and the claws extending through the openings in the sliding door of the outer drum into the interior of the outer drum.

7. A washing machine as claimed in claim 6, wherein the pressure cylinders for connecting the sliding door of the inner drum with the outer drum are arranged on the end walls of the outer drum and the pins on the edge of the end walls of the inner drum, the claws being passed through the end walls of the outer drum.

8. A washing machine ,as claimed in claim 7, wherein limit switches serve for controlling the operation of the couplings and the drive of the inner drum, a supporting member for said limit switches being secured to the outer drum and operating cams on a shaft of the rotatable inner drum being arranged for co-operation with said limit switches.

References Cited by the Examiner UNITED STATES PATENTS 2,033,630 3/1936 Gould 68-139 IRVING BUNEVICH, Primary Examiner. 

1. A DOUBLE-DRUM WASHING MACHINE COMPRISING AN OUTER STATIONARY DRUM, A ROTATABLY DRIVEN INNER DRUM ARRANGED IN SAID OUTER DRUM, A SLIDING DOOR ON SAID OUTER DRUM AND AT LEAST ONE SLIDING DOOR ON THE INNER DRUM, COACTING MEANS ON THE SLIDING DOOR OF THE OUTER DRUM AND THE INNER DRUM TO FORM A COUPLING BETWEEN AND COACTING MEANS BETWEEN THE SLIDING DOOR OF THE INNER DRUM AND THE OUTER DRUM AND OPERABLE UPON ROTATION OF THE INNER DRUM FOR OPENING AND CLOSING SAID INNER DRUM SLIDING DOOR, THE OPENING OF THE SLIDING DOORS BEING EFFECTED BY TWO SUCCESSIVE ROTATIONS OF THE INNER DRUM IN OPPOSITE DIRECTIONS. 